Rosh Chodesh December 2024au. The jewish calendar , which combines both lunar and solar aspects, has 12 months. Rosh chodesh is the name for the first day of every month in the hebrew calendar marked by the appearance of the new moon.
“ rosh chodesh ” means the “head of the new [moon],” and indeed it marks the start of a new lunar month. The month of av is connected to the astrological sign of leo and is the only month ruled by the sun.